Mitsubishi Electric PUHY-200YMF-B Service Handbook page 87

(4) Refrigerant adjustment in heating season
Start
Adjustment
1
Run all the indoor units in the heat-
ing condition in the trial operation
mode.
2
Has the operating
condition stabilized?
3
Is the accumulator's
liquid level AL = 0?
6
Charge with small amounts of re-
frigerant at a time through the low
pressure service port.
After adjusting the refriger-
ant volume, run for 5 min-
utes and judge the AL.
8
Did the liquid level
change from AL = 0
to AL = 1?
0
Finish charging with refrigerant.
B
Determine the difference between
the volume of refrigerant needed for
heating and the volume needed for
cooling and charge with that amount.
C
Turn on switches No. 1, 2, 4, 5 and 6
of the self-diagnosis switch (SW1),
switching to the mode in which the
liquid level is displayed by the LED.
D
Is the accumulator's
liquid level AL = 1?
E
Turn all of switches of
SW1 OFF.
Adjustment
completed.
Note 1
Note 2
4
Is the accumulator's
liquid level AL = 1?
Note 3 5
Is the accumulator's
liquid
level AL=0 when just one indoor
7
Charge with small amounts of re-
frigerant at a time from the low
pressure service port.
9
Did the liquid level
change from AL = 1
A
Finish draining out refrigerant.
Readjust.
Note 3
Note 4
unit is running.
to AL = 0?
* If adjustment of the refrigerant volume was done by heating
operation, it is possible that accumulation of refrigerant due to the
lengthened piping could have a great influence, so it is recom-
mended that operation be checked during the cooling season.
Note: Do not let the drained out refrigerant escape to the outside
atmosphere.
Caution: (PUHY-P200·250YMF-B)
Always be sure to charge with refrigerant from the
liquid phase side.
–85–
for PU(H)Y-(P)200·250YMF-B
Adjustment is
not necessary.
F
Drain out small amount of refrig-
erant at a time from the low pres-
sure service port.
G
Did the liquid level
change from AL = 2
to AL = 1?
H
Finish draining out refrigerant.
I
Draining out approximately 5 kg of
refrigerant.
Adjustment
completed.
YES
NO